With light source devices used in image scanning devices and the like, as light sources increase in output, there is demand for an efficient light source heatsink structure. In the past, light source devices like the following have been proposed.
For example, Patent Literature 1 describes a heatsink structure for an image sensor using a linear light source device, having an LED chip 10 as a light source mounted on a metal plate 11, that dissipates heat from the light source by attaching a curved heatsink 13 to a flat part on the reflecting face side of the LED chip 10.
For example, Patent Literatures 2 to 4 describe a sidelight-type light source device used to illuminate an image scanning device. In a sidelight-type light source device, an LED or other light source is placed on an end of a transparent light guide extending in the main scanning direction of the image scanning device. Light is incident from the end of the light guide, and the incident light is emitted from a side face of the light guide.
Patent Literatures 2 and 3 describe a light source device that places light sources on both end faces of the light guide. Patent Literature 4 describes a light source device that places a light source on one end face of the light guide. In addition, with the light source device described in Patent Literature 2, an optical filter is placed opposite on an end face of the light guide. With the light source device described in Patent Literatures 3 and 4, countermeasures are provided against expansion and contraction due to temperature changes near the light guide.
The light source devices described in Patent Literatures 5 to 9 are an example of a light source device that places a light source on one end face of a light guide. Patent Literature 5 describes a light guide that is tapered at the ends, whereas Patent Literatures 6 to 9 describe a light guide with curved ends. FIG. 10 of Patent Literature 9 illustrates a light source device in which both ends of the light guide are curved, and light sources are placed on both end faces of the curved light guide.
The LED array-type light source devices such as in Patent Literatures 10 to 12 are another example of a light source device used to illuminate an image scanning device. With an LED array-type light source device, light sources such as multiple LEDs are placed in the main scanning direction of the image scanning device. With the light source devices described in Patent Literatures 10 and 11, light emitted from LEDs is guided by a light guide member, and radiated onto a reflector. With the light source device described in Patent Literature 12, light emitted from LEDs is radiated onto a reflector.
Patent Literatures 10 to 12 also describe a reflector (a first reflecting mirror) constituting an image-forming optical system of an image scanning device. FIG. 5 of Patent Literature 11 illustrates a reflector (first reflecting mirror) supported by a carriage of an image scanning device.
Patent Literatures 13 and 14 also describe a reflector (first mirror) supported by a carriage of an image scanning device, and the reflector (first mirror) described in these Patent Literature is supported by a carriage on both ends.